CREDIT QUALITY ASSESSMENT (Impaired Loans by Portfolio) (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2018	Dec. 31, 2017
Financing Receivable Impaired [Line Items]
Average impaired loans for the period	$ 20,802	$ 23,179
Contractual interest income due on impaired loans during the period	649	2,314
Interest income on impaired loans recognized on a cash basis	111	754
Interest income on impaired loans recognized on an accrual basis	46	169
Commercial
Financing Receivable Impaired [Line Items]
Average impaired loans for the period	8,025	7,903
Contractual interest income due on impaired loans during the period	256	828
Interest income on impaired loans recognized on a cash basis	51	204
Interest income on impaired loans recognized on an accrual basis	27	111
All Other
Financing Receivable Impaired [Line Items]
Average impaired loans for the period	2,903	2,968
Contractual interest income due on impaired loans during the period	43	84
Interest income on impaired loans recognized on a cash basis	12	132
Interest income on impaired loans recognized on an accrual basis	13	32
Commercial Real Estate Portfolio Segment \| Commercial Acquisition, Development and Construction
Financing Receivable Impaired [Line Items]
Average impaired loans for the period	136	137
Contractual interest income due on impaired loans during the period	89	333
Interest income on impaired loans recognized on a cash basis	0	0
Interest income on impaired loans recognized on an accrual basis	0	0
Commercial Real Estate Portfolio Segment \| Commercial Investor Real Estate
Financing Receivable Impaired [Line Items]
Average impaired loans for the period	5,694	6,835
Contractual interest income due on impaired loans during the period	156	669
Interest income on impaired loans recognized on a cash basis	4	24
Interest income on impaired loans recognized on an accrual basis	0	0
Commercial Real Estate Portfolio Segment \| Commercial Owner Occupied Real Estate
Financing Receivable Impaired [Line Items]
Average impaired loans for the period	4,044	5,336
Contractual interest income due on impaired loans during the period	105	400
Interest income on impaired loans recognized on a cash basis	44	394
Interest income on impaired loans recognized on an accrual basis	$ 6	$ 26

Loans and Leases Receivable, Impaired, Contractual Interest Income

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- Definition

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+ References

No definition available.

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- Definition

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5258-111524

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- Definition

Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

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+ References

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